Machine for grinding spherical or other curved surfaces



( No Model.)

7 R.-00NRADER., MACHINE FOR GRINDING SPHERIGAL OR OTHERGURVED SURFAO'ES.

No. 51556325? Patented Jan. 30, 1894.

\MtqEE-EEE UN-rrnn STATES PATENT ration.

MACHINE FOR GRINDING SPHERICAL OR OTHER CURVED SURFACES.

SPECIFICATION forming part of Letters Patent No. 513,632, dated January 30, 1894. Application filed October 10,1891. Renewed January 31,l893. Serial Ito- 460,229- (No model.)

To all whom it may concern:

3e it known that I, RUDOLPHWCONRADER, a citizen of the United States, residing at Erie, 1n the county of Erie and State of Pennsylva- 111a, have invented certain new and useful Im: provements in Machines for Grinding and Polishmg Spherical or other Curved Surfaces; and I do hereby declare the following to be a full, clear, and exact description of the inventron, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanylng drawings, and to the letters of reference marked thereon, forming part of this specification. My invention consists in the improvements 1n machines for grinding and polishingspherical and other curved surfaces, hereinafter set forth and explained, and illustrated in the accompanying drawings, in which Flgure 1, is a perspective View of my improved machine for grinding and polishing spherical and other curved surfaces. Fig. 2, 1s a top or plan View of the same. Fig. 3, is a vert-ical longitudinal section of the same. Fig. 4, 1s a vertical transverse section of the same. Fig. 5, is a detail view of a section of one of the ball-chucks of my machine.

In the construction shown in the drawings of mylmproved machine for grinding and polishlng spherical and other curved surfaces, A 1s the bed of the machine frame, and B B the legs .thereof. I

Upon the ends of the bed A are mounted carriages G and O, which carriages slide horizontally in gibs or ways on the bed A, toward and from each other, they being actuated by means of a shaft D one end of which is pro vided with a right hand screw thread and the other end with a left hand screw thread, one of these screw threads engaging with a nut on the carriage O and the other with a nut on the carriage C, so that the rotation of the screw shaft D by means of the crank (1 thereon operates to move the carriages C and O simultaneously toward or from each other at a uniform speed, according to the direction the screw shaft D is rotated.

In bearings c and c on the carriages C and C, I mount shafts E and E in line with each other, which shafts are provided with driving pulleys F and F, and on the inner ends brought together.

of the shafts E and E I secure ball-chucks G, adapted to clamp a ball I between them,

as and for the purpose hereinafter set forth. These chucks G are made laterally adjustable so that their centers may be moved out of line withthe centers of the shafts E and E, so as to center the ball to one side of the centers of the said shafts, for the purpose of so holding the ball that a depression on one side thereof may be ground out without cutting away the opposite side of the ball to any great degree, so that when the depression is removed and the ball again finished it will be only reduced in diameter to the extent of the depth of the depression removed from the side thereof.

The center part of the bed A is cut away at the front side thereof, and transverse guides I I are secured to the lower side of the bed A, in which are mounted atransversely sliding carriage J, adapted to be adj usted transversely in said guides I I as desired and secured at any point by means of set screwst'r'.

In the carriage J is mounted a vertical shaft, consisting of an upper section K and a lower section K, this shaft being directly beneath the point where the chucks G G on the ends of the shafts E and E would meet if lhe upper section K of this vertical shaft is mounted in along sleeve bearing 75 in the upper part of the carriage J and the lower section K in bearings in the lower part of the carriage J, and is connected with a driving pulley L by means of an ordinary spline and groove a, so that the shaft section K is adapted to be moved vertically in the pulley L; and on the lower end of the upper shaft section K and on the upper end of the lower shaft section K are friction collars and plates Z Z, and in grooves in these oted short lever c which engages with the outer end of the lever e the inner end of which engages with a groove in the collar Z on the upper end of the lower shaft section tion thereof ground into shape.

K, so that when the outer ends of the levers e and e are brought together the friction plates Z Z are also forced together so that the upper shaft section K is rotated by means of the frictional contact of the plates Z Z. This operates to rotate a cup shaped tool M, on the upper end of the upper shaft section K, against a ball H held between the ball chucks G G. This cup shaped tool M I make either in the form of a cutting tool, a grinding tool, or a polishing tool, as desired, said tools M being interchangeable on the shaft K.

On the carriage J and pivoted around the sleeve shaped shaft bearing 70 is an arm N adapted to swing around a central point, the center of which is the center of the vertical shaft K. From this arm N an arm N projects downward to a point opposite the driving pulley L on the lower shaft section K, where it is provided with bearings in which small idler pulleys n n operate, as and for the purpose hereinafter set forth.

On the arm N is mounted a carriage 0 adapted to be moved in and out on gibs or ways m in the arm N by means of an adjnsting screw 0%.

In bearings on the carriage O is mounted an emery wheel P the shaft of which is provided with driving pulleys p from which driving belts 10 pass down around the idler pulleys n n to and around the vertical driving pulley L which pulley is in turn driven by a belt Q passing around idlers q q to and around a driving pulley R on a shaft R, mounted in bearings r a" at the back of the machine, to the shaft of which pulley power is supplied in any convenient manner. It will be ob served that by this arrangement the emery wheel P can be continuously driven at any desired speed, the arm N supporting the same being at the same time adapted to be moved around the axis 70 thereof so that the emery wheel P travels in a semicircular path around the ball H held between and rotated -by the chucks G G. i

In operation the rough ball is first clamped between the chucks G G and the major por- The ball is then reversed and clamped by its opposite sides, and the portions which were first occupied by the chucks G G are then ground to shape and finally the ball is polished by means of a rotating polishing tool M held up against it, as it is rotated and operated as hereinbefore described.

Having thus fully described my invention, so as to enable others to construct and operate the same, what I claim as new, and desire to secure by Letters Patent of the United States, is-

1. The combination in a machine for grinding and polishing spherical and other curved surfaces, of shafts as E E having adjustable ball ch ueks G G thereon, with a vertical shaft as K K having a cup shaped tool as M on the upper end thereof adapted to operate upon a ball as H held between the ball chucks G G substantially as and for the purpose set forth.

2. The combination ina machine for grinding and polishing spherical and other curved surfaces, of a vertical shaft consisting of the sections as K K, the upper end of the section K being provided with a cup shaped tool M and the lower section K with a pulley secured thereto by means of a spline or groove so that the shaft will move longitudinally therein with friction collars or plates as ll on the ends of said shafts and levers as e and e, substantially as and for the purpose set forth.

3. The combination in a machine for grinding and polishing spherical and other curved surfaces, of shafts as E E provided with chucks as G G, and adapted to be moved longitudinally toward and from a common center, an arm as Nswinging horizontally on an axis central with the meeting point of the chucks G G, a vertical driving pulley as L with a grinding wheel as P idler pulleys as 'n n and belts as p from said vertical driving pulley passing around the idlers n n to pulleys p p on the grinding wheel mounted upon said swinging arm and adapted to travel horizontally in a semi-circle around a ball held between the chucks G G, substantially as and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

RUDOLPH ooNRAnER.

Witnesses:

H. J. CURTZE, O. F. BERNEITTER. 

